No Amiibo-exclusive content in Super Mario Odyssey
You can unlock every suit without them.
Super Mario Odyssey will of course be compatible with several Amiibos, including three new ones featuring Mario, Peach, and Bowser in wedding suits. If you place the Amiibo on the Joy-Con, you will gain access to a special power (like temporary invincibility) and also several in-game suits. You can, however, get these suits while you play, with no Amiibo required.
While the Amiibo should get instant access to these suits, we're guessing you will need to earn them or find them while playing to get them without, but it's nice to know there's no exclusive content locked to the figurines. Super Mario Odyssey and the new Amiibos will be available on October 27, exclusively on Nintendo Switch. You can read more about the Amiibos here and our hands-on impressions here.